U.S. patent number 10,486,657 [Application Number 15/053,949] was granted by the patent office on 2019-11-26 for pump for integrated brake system.
This patent grant is currently assigned to MANDO CORPORATION. The grantee listed for this patent is MANDO CORPORATION. Invention is credited to Jin Seok Kim, Weon Chan Ko.
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United States Patent |
10,486,657 |
Ko , et al. |
November 26, 2019 |
Pump for integrated brake system
Abstract
Disclosed herein is a pump of an integrated brake system. The
pump includes a motor, a gear unit which converts a rotating force
of the motor into linear reciprocating movement, a piston assembly
which is connected to the gear unit and reciprocates based on power
conversion of the gear unit, a piston housing which accommodates
the piston assembly, and a fixed rod fixedly disposed in the piston
housing in a longitudinal direction. Here, the piston assembly
includes a coupling groove formed therein, into which the fixed rod
is inserted.
Inventors: |
Ko; Weon Chan (Gyeonggi-do,
KR), Kim; Jin Seok (Gyeonggi-do, KR) |
Applicant: |
Name |
City |
State |
Country |
Type |
MANDO CORPORATION |
Gyeonggi-do |
N/A |
KR |
|
|
Assignee: |
MANDO CORPORATION (Gyeonggi-Do,
KR)
|
Family
ID: |
56682767 |
Appl.
No.: |
15/053,949 |
Filed: |
February 25, 2016 |
Prior Publication Data
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Document
Identifier |
Publication Date |
|
US 20160251007 A1 |
Sep 1, 2016 |
|
Foreign Application Priority Data
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|
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Feb 26, 2015 [KR] |
|
|
10-2015-0027519 |
|
Current U.S.
Class: |
1/1 |
Current CPC
Class: |
F04B
9/02 (20130101); F04B 35/01 (20130101); B60T
13/745 (20130101); F04B 17/03 (20130101); F04B
53/146 (20130101); B60T 1/10 (20130101); B60T
17/02 (20130101); B60T 7/042 (20130101) |
Current International
Class: |
B60T
1/10 (20060101); B60T 13/74 (20060101); F04B
9/02 (20060101); B60T 7/04 (20060101); B60T
17/02 (20060101); F04B 53/14 (20060101); F04B
35/01 (20060101); F04B 17/03 (20060101) |
Field of
Search: |
;417/415 ;188/156,157
;92/32,165PR ;74/840,841,842,22A |
References Cited
[Referenced By]
U.S. Patent Documents
Foreign Patent Documents
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203926862 |
|
Nov 2014 |
|
CN |
|
105221614 |
|
Jan 2016 |
|
CN |
|
202015105391 |
|
Oct 2015 |
|
DE |
|
102014212417 |
|
Dec 2015 |
|
DE |
|
10-2005-0004279 |
|
Jan 2005 |
|
KR |
|
Other References
Office Action dated Nov. 28, 2018 for Chinese Application No.
201610190480.1 and its English machine translation by Google
Translate. cited by applicant .
Notification to Grant dated Mar. 29, 2019 for Chinese Application
No. 201610190480.1 and its English translation from Global Dossier.
cited by applicant.
|
Primary Examiner: Kramer; Devon C
Assistant Examiner: Brunjes; Christopher J
Attorney, Agent or Firm: Ladas & Parry, LLP
Claims
What is claimed is:
1. A pump of an integrated brake system, comprising: a motor; a
gear unit which converts a rotating force of the motor into linear
reciprocating movement; a piston assembly which is connected to the
gear unit and reciprocates based on power conversion of the gear
unit; a piston housing which accommodates the piston assembly; and
a fixed rod fixedly disposed in the piston housing in a
longitudinal direction, wherein the piston assembly comprises a
coupling groove formed therein, into which the fixed rod is
inserted, wherein the piston assembly comprises a piston head, a
spindle, and a rotation-preventing ring disposed between the piston
head and the spindle to prevent rotation of the piston assembly,
and wherein the piston head is configured to reciprocate in a
cylinder formed in the piston housing, the spindle has one side
inserted into and coupled with an insertion groove formed in one
side of the piston head, and a ring member is disposed on an outer
circumferential surface of the spindle.
2. The pump of claim 1, wherein the piston housing comprises a
through hole formed in an end thereof to allow the fixed rod to be
inserted thereinto and coupled therewith.
3. The pump of claim 2, further comprising a fixing member which is
coupled with a portion of the fixed rod which passes through the
through hole and is exposed to fix the fixed rod.
4. The pump of claim 1, wherein a cross section of the fixed rod is
formed in a polygonal shape, and wherein the coupling groove is
formed corresponding to the cross section of the fixed rod.
5. The pump of claim 1, wherein a hollow is formed in the motor,
wherein the gear unit comprises a nut which is restricted by and
coupled with a rotor of the motor and rotates based on rotation of
the rotor, and wherein the piston assembly is disposed in the nut
and reciprocates based on rotation of the nut.
6. The pump of claim 5, wherein the motor is coupled with one side
of the piston housing and a through hole is formed in the other
side of the piston housing.
7. The pump of claim 5, further comprising: a motor housing which
accommodates the motor; and a four-point contact bearing disposed
between the motor housing and the rotor.
8. The pump of claim 7, wherein the motor housing and the piston
housing are assembled based on a position of the four-point contact
bearing.
9. The pump of claim 5, wherein: the spindle is screw-coupled with
the nut.
10. The pump of claim 9, wherein a holding protrusion is formed on
an inner circumferential surface of the piston head, and wherein
the spindle is inserted into the insertion groove until the ring
member is held by the holding protrusion and then coak-coupled with
one side of the piston head to fix the spindle to the piston
head.
11. The pump of claim 9, wherein a holding groove is formed in an
inner circumferential surface of the piston head, and wherein the
spindle is inserted into the insertion groove until the ring member
is held by the holding groove to fix the spindle to the piston
head.
12. The pump of claim 9, wherein the rotation-preventing ring is
disposed in the insertion groove and formed corresponding to the
fixed rod, and wherein the spindle comprises an accommodation
groove formed in one side thereof, Which accommodate the
rotation-preventing ring.
13. The pump of claim 1, wherein the rotation-prevention ring has a
shape corresponding to the fixed rod so that the fixed rod prevents
the rotation of the piston assembly.
14. The pump of claim 1, further comprising: a motor housing
accommodating the motor; and a bearing disposed between the motor
housing and the piston housing.
Description
CROSS-REFERENCE TO RELATED APPLICATION
This application claims priority to and the benefit of Korean
Patent Application No. 10-2015-0027519, filed on Feb. 26, 2015, the
disclosure of which is incorporated herein by reference in its
entirety.
BACKGROUND
1. Field of the Invention
The present invention relates to a pump of an integrated brake
system, and more particularly, to a pump applied to an integrated
brake system, which generates a braking pressure using an electric
motor as a power source depending on a brake pedal operation of a
driver and vehicle conditions.
2. Discussion of Related Art
Recently, to increase fuel efficiency and to reduce emissions,
hybrid vehicles, fuel cell vehicles, electric vehicles, etc. have
been vigorously developed. These vehicles essentially include
brakes, that is, brakes of brake systems installed therein. Here, a
brake for a vehicle indicates a device which reduces a speed of a
traveling vehicle or stops the vehicle.
General brakes of brake systems for vehicles include vacuum brakes
which generate a braking force using suction pressure of an engine
and hydraulic brakes which generate a braking force using hydraulic
pressure.
Vacuum brakes are devices which provide a great braking force with
a small force using a pressure difference between suction pressure
of a vehicle engine and atmospheric pressure in a vacuum booster.
That is, it is a device which generates an output much greater than
a force applied to a pedal when a driver presses the pedal.
In conventional vacuum brakes described above, it is necessary to
supply suction pressure of a vehicle engine to a vacuum booster to
form a vacuum and thus fuel efficiency is reduced. Also, even when
a vehicle stops, it is necessary to constantly drive an engine to
form a vacuum. Also, since fuel cell vehicles and electric vehicles
do not include an internal combustion engine, it is impossible to
apply conventional vacuum brakes which amplify a pedal effort of a
driver during braking. In case of hybrid vehicles, in order to
increase fuel efficiency, it is necessary to provide an idling stop
function when a vehicle stops. Accordingly, it is necessary to
apply hydraulic brakes.
That is, as described above, it is necessary to perform
regenerative braking to increase fuel efficiency in all vehicles.
However, when a hydraulic brake is applied, the regenerative
braking is easily performed.
Meanwhile, an electro-hydraulic brake system, a hydraulic type
brake, is a brake system in which when a driver presses a pedal, an
electronic control unit senses it and supplies hydraulic pressure
to a master cylinder, thereby transferring braking hydraulic
pressure to each wheel and generating a braking force.
Recently, integrated brake systems in which a pump, a control unit,
and a valve which form an electro-hydraulic brake system are
integrated in one module have been developed. Since the integrated
brake systems described above are formed by integrating necessary
units as one, products have large sizes and are inconvenient to be
mounted in vehicles.
The following prior art document discloses a structure for
preventing rotation of a ball screw bar of a steering device for a
vehicle, in which the ball screw bar is restrained from rotating
together with a motor when the motor rotates to prevent wheels from
being degraded in performance but does not disclose technical
features of the present invention.
PRIOR ART DOCUMENT
Patent Document
Korean Patent Publication No. 10-2005-0004279
SUMMARY OF THE INVENTION
The present invention is direct to a pump of an integrated brake
system, capable of increasing the degree of freedom in design of a
vehicle by reducing a length of a cylinder in which a piston
reciprocates.
The present invention is also directed to a pump of an integrated
brake system, capable of being precisely controlled by allowing
rotational movement of a motor to be reflected in linear movement
of a piston.
The aspects of the present invention are not limited to the above
description. Additional aspects of the invention will be set forth
in part in the description which follows and, in part, will be
obvious from the description, or may be learned by practice of the
invention.
According to an aspect of the present invention, there is provided
a pump of an integrated brake system. The pump includes a motor, a
gear unit which converts a rotating force of the motor into linear
reciprocating movement, a piston assembly which is connected to the
gear unit and reciprocates based on power conversion of the gear
unit, a piston housing which accommodates the piston assembly, and
a fixed rod fixedly disposed in the piston housing in a
longitudinal direction. Here, the piston assembly includes a
coupling groove formed therein, into which the fixed rod is
inserted.
The piston housing may include a through hole formed in an end
thereof to allow the fixed rod to be inserted thereinto and coupled
therewith. A portion of the fixed rod which passes through the
through hole and is exposed may be coupled with a fixing member to
fix the fixed rod.
A cross section of the fixed rod may be formed in a polygonal
shape, and the coupling groove may be formed corresponding to the
cross section of the fixed rod.
A hollow may be formed in the motor, the gear unit may include a
nut which is restricted by and coupled with a rotor of the motor
and rotates based on rotation of the rotor, and the piston assembly
may be disposed in the nut and may reciprocate based on rotation of
the nut.
The pump may further include a motor housing which accommodates the
motor and a four-point contact bearing disposed between the motor
housing and the rotor.
The motor housing and the piston housing may be assembled based on
a position of the four-point contact bearing.
The piston assembly may include a piston head which reciprocates in
a cylinder formed in the piston housing and a spindle which has one
side inserted into and coupled with an insertion groove formed in
one side of the piston head and is screw-coupled with the nut.
Also, a ring member may be disposed on an outer circumferential
surface of the spindle.
A holding protrusion may be formed on an inner circumferential
surface of the piston head, and the spindle may be inserted into
the insertion groove until the ring member is held by the holding
protrusion and then coak-coupled with one side of the piston head
to fix the spindle to the piston head.
A holding groove may be formed in an inner circumferential surface
of the piston head, and the spindle may be inserted into the
insertion groove until the ring member is held by the holding
groove to fix the spindle to the piston head.
The piston assembly may further include a rotation-preventing plate
disposed in the insertion groove and formed corresponding to the
fixed rod. Also, the spindle may include an accommodation groove
formed in one side thereof, which accommodates the
rotation-preventing plate.
The gear unit may include a worm shaft coaxially connected to a
rotating shaft of the motor, a worm wheel which is engaged with the
worm shaft and rotates based on rotation of the worm shaft, a
pinion disposed coaxially with the worm wheel, and a rack bar which
is engaged with the pinion and linearly reciprocates based on
rotation of the pinion.
BRIEF DESCRIPTION OF THE DRAWINGS
The above and other objects, features and advantages of the present
invention will become more apparent to those of ordinary skill in
the art by describing in detail exemplary embodiments thereof with
reference to the accompanying drawings, in which:
FIG. 1 is a cross-sectional view of a pump of an integrated brake
system in accordance with one embodiment of the present
invention;
FIG. 2 is a perspective view illustrating an example of a fixed rod
among components of the pump of the integrated brake system in
accordance with one embodiment of the present invention;
FIGS. 3(a) and 3(b) are cross-sectional views of the fixed rod
shown in FIG. 2;
FIG. 4 is a perspective view illustrating another example of the
fixed rod among components of the pump of the integrated brake
system in accordance with one embodiment of the present
invention;
FIGS. 5(a) and 5(b) are cross-sectional views of the fixed rod of
FIG. 4;
FIGS. 6(a) to 6(c) are views illustrating an example of a process
of assembling a piston head with a spindle among components of the
pump of the integrated brake system in accordance with one
embodiment of the present invention; and
FIGS. 7(a) to 7(c) are views illustrating another example of the
process of assembling the piston head with the spindle among
components of the pump of the integrated brake system in accordance
with one embodiment of the present invention.
DETAILED DESCRIPTION OF EXEMPLARY EMBODIMENTS
Exemplary embodiments of the present invention will be described
with reference to the drawings. Throughout the specification, like
reference numerals designate like elements and a repetitive
description thereof will be omitted.
Also, when it is determined that a detailed description of publicly
known related art may make the points of the present embodiment
unclear, the detailed description thereof will be omitted. Also, it
should be understood that the attached drawings are merely to allow
the concept of the present invention to be easily understood and
the concept of the present invention is not limited by the attached
drawings.
Hereinafter, referring to FIGS. 1 to 5(b), a pump of an integrated
brake system in accordance with one embodiment of the present
invention will be described. FIG. 1 is a cross-sectional view of
the pump of the integrated brake system in accordance with one
embodiment of the present invention. FIGS. 2 to 3(b) are a
perspective view and cross-sectional views illustrating an example
of a fixed rod among components of the pump of the integrated brake
system in accordance with one embodiment of the present invention.
FIGS. 4 to 5(b) are a perspective view and cross-sectional views
illustrating another example of the fixed rod among components of
the pump of the integrated brake system in accordance with one
embodiment of the present invention.
The pump of the integrated brake system in accordance with one
embodiment of the present invention, as shown in FIG. 1, includes a
motor 100, a nut 200, a piston assembly 300, a piston housing 400,
and a fixed rod 500.
The motor 100 is a component which receives power to rotate. An
electronic control unit (ECU) controls an operation of the motor
100 based on an external environment or a pressure applied by a
user onto a brake pedal. A hollow is formed in the motor 100, and a
rotor 120 is disposed in the hollow. Accordingly, when the motor
100 operates, the rotor 120 formed in the hollow of the motor 100
is allowed to rotate. Also, the motor 100 may include a motor
housing 110 for accommodating and protecting internal components
thereof and four-point contact bearings 130 disposed between the
motor housing 110 and the rotor 120.
The nut 200 is a component which rotates based on the rotation of
the motor 100. In detail, the rotor 120 is disposed in the hollow
of the motor 100 and rotates when power is applied to the motor
100. The nut 200 also rotates based on the rotation of the rotor
120. A hollow is formed in the nut 200 and the piston assembly 300
which will be described below is inserted into the nut 200, thereby
ball-screw-coupling the nut 200 with the piston assembly 300. That
is, a groove corresponding to a screw thread formed on an inside of
the nut 200 is formed on an outer circumferential surface of the
piston assembly 300 and rotational power of the motor 100 may be
converted into linear reciprocating movement by the
ball-screw-coupling structure described above. In the end, the nut
200 and the groove formed on the outer circumferential surface of
the piston assembly 300 perform a function of a gear unit which
converts rotational movement of the motor 100 into linear movement.
Meanwhile, a damping member may be disposed between the rotor 120
and the nut 200, through which vibrations of the motor 100 are
prevented from being transferred to the nut 200 and the piston
assembly 300, thereby protecting the piston assembly 300 when the
motor 100 is overloaded.
The piston assembly 300 is a component disposed in the nut 200 and
reciprocates when the nut 200 rotates based on the rotation of the
motor 100. In case of the piston assembly 300, as shown in FIG. 1,
the screw thread is formed on the inside of the nut 200 and a part
of the piston assembly 300 coupled with the inside of the nut 200
includes a screw thread corresponding to the screw thread formed on
the inside of the nut 200. Accordingly, when the nut 200 rotates,
the piston assembly 300 is allowed to linearly reciprocate. Also, a
coupling groove 330 is formed in the piston assembly 300 to allow
the fixed rod 500 which will be described below to be inserted
thereinto, which will be described below in detail.
Meanwhile, the piston assembly 300, in detail, includes a piston
head 310 and a spindle 320. The piston head 310 is a component
which generates hydraulic pressure by reciprocating a cylinder
formed by the piston housing 400, which will be described below.
The piston head 310 may include at least one sealing member 311 to
prevent leakage of a fluid in the cylinder and a slip ring 312 on
an outer circumferential surface thereof to smoothly reciprocate.
The piston head 310 and the spindle 320 described above may be
integrally formed or may be separately formed and mutually
assembled to form the piston assembly 300, which will be described
below in detail.
The piston housing 400 is a component which accommodates the piston
assembly 300 and has one side coupled with the motor housing 110
which accommodates the motor 100 and the other side which forms the
cylinder with the fluid accommodated therein to allow the piston
head 310 to reciprocate and generate the hydraulic pressure.
Meanwhile, coupling between the piston housing 400 and the motor
housing 100 may be performed based on a location of the four-point
contact bearing 130 described above. This is because the bearing
130 is accurately manufactured to precisely align the piston
housing 400 with the motor housing 110. Through this, since it is
possible to provide a precise linear path when the piston assembly
300 reciprocates, when the piston assembly 300 reciprocates in the
cylinder, damage to an inner wall of the cylinder may be minimized
and hydraulic pressure may be efficiently generated at the same
time.
The fixed rod 500 is a component fixed in the piston housing 400 in
a longitudinal direction. As described above, since the fixed rod
500 is inserted into the coupling groove 330 formed in the piston
assembly 300, the piston assembly 300 is allowed to linearly
reciprocate in the pump along the fixed rod 500. Through this, it
is possible to provide reciprocating linearity of the piston
assembly 300. Also, the coupling groove 330 is formed in the piston
assembly 300 to allow the fixed rod 500 to be inserted thereinto
and to slide. The coupling groove 330, as shown in FIG. 1, may
extend to the hollow of the motor 100. Through this, since it is
possible to reduce a size of the pump and to provide a
reciprocating distance of a piston to generate full hydraulic
pressure, a vehicle-mounting property may be increased.
In addition, it is necessary to fix the fixed rod 500 to the piston
housing 400. Here, the fixed rod 500 and the piston housing 400 may
be integrally formed together or separately manufactured and fixed
by coupling therebetween. Particularly, as shown in FIG. 1, a
through hole may be formed in the other side of the piston housing
400 to allow the fixed rod 500 to be inserted thereinto and coupled
therewith and a portion of the fixed rod 500 which passes through
the through hole and is exposed may be coupled with an additional
fixing member 510 to fix the fixed rod 500 to be fixedly coupled
with the piston housing 400. For this, a screw thread is formed on
an outer circumferential surface of the portion of the fixed rod
500 which passes through the through hole and is exposed and a nut
member is used as the fixing member 510, thereby screw-fastening
both components to be coupled and fixed to each other. Also, an
O-ring 410 for effectively supporting the fixed rod 500 may be
disposed at the through hole. However, in case of the coupling
described above, it is necessary to dispose an additional sealing
member to prevent the leakage of the fluid accommodated in the
piston housing 400 from the through hole.
Meanwhile, as described above, the spindle 320 is ball-screw
coupled with the nut 200 and linearly reciprocates based on the
rotation of the nut 200. Here, when the spindle 320 rotates along
with the nut 200, the piston assembly 300 is not allowed to
smoothly reciprocate in the cylinder. To prevent this, a cross
section of the fixed rod 500 may not be formed in a circular shape
and a cross section of the coupling groove 330 of the piston
assembly 300 may be formed corresponding to the shape of the cross
section of the fixed rod 500. In detail, as shown in FIGS. 2 and 3,
the cross section of the fixed rod 500 is formed in a polygonal
shape and the coupling groove 330 is formed corresponding thereto.
When the fixed rod 500 and the coupling groove 330 are formed as
described above and the spindle 320 rotates based on the rotation
of the nut 200, as shown in FIG. 3(b), an inner wall of the
coupling groove 330 formed in the spindle 320 is in contact with
the fixed rod 500, thereby preventing the piston assembly 300 from
further rotating. In addition, as shown in FIGS. 4 to 5(b), when
the cross section of the fixed rod 500 is formed to include a
plurality of protrusions and the coupling groove 330 is formed
corresponding thereto, an allowable radius of rotation of the
piston assembly 300 may be further reduced compared with the
example of the fixed rod 500 shown in FIGS. 2 to 3(b).
Meanwhile, the piston assembly 300 in the pump of the integrated
brake system in accordance with one embodiment of the present
invention includes the piston head 310 and the spindle 320 as
described above, both of these components may be integrally
manufactured to form the piston assembly 300 but may be separately
manufactured and then assembled with each other to form the piston
assembly 300. Hereinafter, referring to FIGS. 6(a) to 7(c),
examples of assembling the piston head 310 with the spindle 320 in
the integrated brake system in accordance with one embodiment of
the present invention will be described. FIGS. 6(a) to 6(c) are
views illustrating an example of a process of assembling the piston
head 310 with the spindle 320 among the components of the pump of
the integrated brake system in accordance with one embodiment of
the present invention. FIGS. 7(a) to 7(c) are views illustrating
another example of a process of assembling the piston head 310 with
the spindle 320 among the components of the pump of the integrated
brake system in accordance with one embodiment of the present
invention.
As shown in FIGS. 6(a) to 6(c), the piston assembly 300 in the pump
of the integrated brake system in accordance with one embodiment of
the present invention includes the piston head 310 and the spindle
320. An insertion groove is formed in one side of the piston head
310, and a holding protrusion is formed on an inner circumferential
surface, that is, one side of the insertion groove. Also, a coak
portion 313 formed with a small thickness is formed at an end of
the piston head 310 in a direction in which the spindle 320 is to
be inserted as shown in FIG. 6(a). Meanwhile, a ring member 322
such as a C-ring or O-ring is disposed on an outer circumferential
surface of the spindle 320, and as shown in FIG. 6(b), the spindle
320 is inserted into the insertion groove of the piston head 310.
The coak portion 313 is compressed inward while the ring member 322
is held by the holding protrusion and not further inserted, thereby
coak-coupling the piston head 310 with the spindle 320 to fixedly
couple both components, which may be checked in detail with
reference to FIG. 6(c) which is an enlarged view of a part shown in
FIG. 6(b). In addition, to prevent the fluid in the cylinder from
leaking into the spindle 320 and the motor 100 after coupling, an
additional sealing member 323 may be further disposed on the outer
circumferential surface of the spindle 320.
In another example of the process of assembling the piston head 310
with the spindle 320 among components of the pump of the integrated
brake system shown in FIGS. 7(a) to 7(c), like the example of the
assembling process shown in FIGS. 6(a) to 6(c), the spindle 320
including the outer circumferential surface on which the ring
member 322 is disposed is inserted into the insertion groove of the
piston head 310. However, unlike the example of the assembling
shown in FIGS. 6(a) to 6(c), a holding groove 315 is formed in an
inner circumferential surface of the piston head 310 and the
spindle 320 is inserted into the insertion groove until the ring
member 322 is held by the holding groove 315, thereby fixedly
coupling the spindle 320 with the piston head 310.
Meanwhile, a rotation-preventing plate 340 may be disposed between
the piston head 310 and the spindle 320. In detail, the
rotation-preventing plate 340 is disposed in the insertion groove
formed in the piston head 310 and includes a hole corresponding to
the cross section of the fixed rod 500. Also, an accommodation
groove 321 capable of accommodating the rotation-preventing plate
340 is formed at one side of the spindle 320. When configured as
described above, it is unnecessary to accurately process the entire
through hole formed lengthwise in the spindle 320 in the
longitudinal direction to correspond to the cross section of the
fixed rod 500. Also, since it is necessary to accurately process
only the hole formed at the rotation-preventing plate 340,
processing costs may be reduced.
In case of the pump of the integrated brake system in accordance
with one embodiment of the present invention described above, the
gear unit which converts the rotational movement of the motor 100
into the linear movement has been described as an example of
ball-screw coupling. However, another power conversion method may
be available. In detail, when the motor 100 is not a hollow type
motor, the gear unit may include a worm shaft coaxially connected
to a rotating shaft of the motor 100, a worm wheel which is engaged
with the worm shaft and rotates based on rotation of the worm
shaft, a pinion disposed coaxially with the worm wheel, and a rack
bar which is engaged with the pinion and linearly reciprocates
based on rotation of the pinion.
The rack bar may be separately formed from the piston assembly 300
described above and coupled by assembling both components or may be
integrally formed. Through the components of the gear unit
described above, the respective components in the integrated brake
system can be freely arranged, and the vehicle mounting property
and the degree of freedom in design can be secured.
In accordance with one embodiment of the present invention, a pump
of an integrated brake system can reduce a size of the integrated
brake system by disposing a nut in a hollow inside of a motor and
coupling the nut with a piston in a ball-screw method to allow the
piston to linearly reciprocate in the cylinder when the nut
rotates.
Also, a fixed rod is disposed in the cylinder and a coupling groove
into which the fixed rod is inserted is formed in the piston to
provide linear reciprocating movement of the piston, thereby
preventing an inner wall of the pump from being damaged and
allowing the piston to smoothly move.
The effects of the present invention are not limited to the above
disclosure. Additional effects not stated above may become apparent
to those of ordinary skill in the art based on the following
descriptions.
The embodiments described above and the attached drawings are
merely examples of the technical concept of the present invention.
Accordingly, since the embodiments described above are not to limit
but to explain the technical concept of the present invention, it
is obvious that the scope of the technical concept of the present
invention is not limited thereto. It will be understood by those of
ordinary skill in the art that various changes in form and details
may be made therein without departing from the scope of the
technical concept of the present invention as defined by the
following claims.
* * * * *